Constellation and Amazon announced a 20-year power purchase agreement at the Calvert Cliffs nuclear plant in Lusby, Maryland, on September 30, 2026. According to Constellation’s announcement, the agreement covers 690 megawatts of power from the plant, including a new 190 megawatt uprate that Constellation expects to bring online between 2030 and 2032.
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What the agreement covers
Constellation describes the arrangement as two parts: a long-term power purchase agreement and a “related retail supply agreement” that supports Amazon operations in the 13-state PJM market.
| Item | As stated by Constellation |
|---|---|
| Owner and operator | Constellation |
| Buyer | Amazon |
| Site | Calvert Cliffs, Lusby, Maryland |
| Plant capacity | 1,790 MW |
| Contracted power | 690 MW, including the 190 MW uprate |
| New capacity | Approximately 190 MW, online between 2030 and 2032 |
| Term | 20 years |
| Investment | More than $3 billion in Maryland infrastructure |
An uprate raises the output of an existing plant. Constellation says the agreement enables the 190 MW uprate and gives it the revenue certainty to pursue its plan “to relicense the plant for another 20 years.”
The plant and the grid
Calvert Cliffs is a 1,790-megawatt plant. Constellation says it produces approximately 80% of Maryland’s clean energy, employs more than 800 people and contributes about $21 million a year in taxes. The plant continues to serve the PJM regional grid.
Chief executive Joe Dominguez said the agreement “demonstrates how private investment can strengthen critical energy infrastructure.”
What changes
The 690 MW volume combines output the plant already produces with roughly 190 MW of new capacity that the agreement helps finance. On Constellation’s stated schedule, the new megawatts arrive between 2030 and 2032, so until then the agreement is a contracted supply arrangement for existing output. Amazon’s supply runs through the retail agreement across the 13-state PJM market.
The agreement also extends the planning horizon for the plant itself: a 20-year offtake contract lines up with the 20-year relicensing Constellation intends to pursue, alongside the more than $3 billion it says it will invest in Maryland infrastructure.
Power agreements of this kind are tracked alongside data-center campuses and compute contracts in The Model Press AI data-center project tracker.
